System and method for lithography simulation

Abstract

In one aspect, the present invention is directed to a technique of, and system for simulating, verifying, inspecting, characterizing, determining and/or evaluating the lithographic designs, techniques and/or systems, and/or individual functions performed thereby or components used therein. In one embodiment, the present invention is a system and method that accelerates lithography simulation, inspection, characterization and/or evaluation of the optical characteristics and/or properties, as well as the effects and/or interactions of lithographic systems and processing techniques.

What is claimed is: 
     
       1. A method implemented by a computer, the method comprising:
 receiving data corresponding to a first design, the data including a plurality of polygons; 
 converting, using the computer, the data into a pixel-based representation of the first design; 
 identifying first and second different potential process window conditions; 
 processing, using the computer, the pixel-based representation to obtain first and second simulated images respectively corresponding to the first and second potential process window conditions; and 
 analyzing, using the computer, the first and second simulated images to determine deviations from a target design at the first and second potential process window conditions. 
 
     
     
       2. A method according to  claim 1 , wherein processing includes using a model of an imaging path of projection and illumination optics of a photolithographic process for imaging the first design. 
     
     
       3. A method according to  claim 2 , further comprising determining a critical dimension sensitivity of the first design to a change in at least one process parameter of the photolithographic process. 
     
     
       4. A method according to  claim 3 , wherein determining the critical dimension sensitivity of the design pattern on the photolithographic mask to the change in the at least one process parameter of the photolithographic process further includes determining a plurality of derivatives as the critical dimension sensitivity of the first design. 
     
     
       5. A method according to  claim 3 , wherein the change in the at least one process parameter of the photolithographic process is a change in focus, illumination dose, numerical aperture or illumination aperture. 
     
     
       6. A method according to  claim 3 , wherein analyzing includes determining a configuration of settings of the photolithographic process using a comparison of the first and second simulated images to the target design. 
     
     
       7. A method according to  claim 6 , wherein the configuration of settings include at least one of focus, illumination dose, numerical aperture or illumination aperture. 
     
     
       8. A method according to  claim 2 , wherein the model comprises coefficient matrices representing the imaging path of the projection and illumination optics of the photolithographic process. 
     
     
       9. A method according to  claim 8 , wherein the coefficient matrices are representative of one or more of a focus, dose, numerical aperture, illumination aperture, and aberration of the photolithographic process. 
     
     
       10. A method according to  claim 1 , further comprising:
 receiving data corresponding to a second design, the data including a second plurality of polygons; 
 converting, using the computer, the data into a pixel-based representation of the second design; 
 processing, using the computer, the pixel-based representation to obtain third and fourth simulated images respectively corresponding to the first and second potential process window conditions; and 
 analyzing, using the computer, the third and fourth simulated images to determine deviations from the target design at the first and second potential process window conditions. 
 
     
     
       11. A method according to  claim 10 , wherein the second design comprises alterations to the first design. 
     
     
       12. A method according to  claim 11 , wherein the alterations comprise resolution enhancement techniques (RET). 
     
     
       13. A method according to  claim 11 , wherein the alterations comprise optical proximity correction (OPC) techniques. 
     
     
       14. A method according to  claim 11 , wherein the alterations comprise phase shift mask (PSM) techniques. 
     
     
       15. A method according to  claim 1 , wherein the first and second potential process window conditions comprise different first and second defocus values, respectively. 
     
     
       16. A method according to  claim 1 , wherein the first and second potential process window conditions comprise different first and second exposure dose values, respectively. 
     
     
       17. A computer program product comprising non-transitory computer-readable storage media bearing instructions which, when executed by a computer, cause the computer to perform a method comprising:
 receiving data corresponding to a first design, the data including a plurality of polygons; 
 converting, using the computer, the data into a pixel-based representation of the first design; 
 identifying first and second different potential process window conditions; 
 processing, using the computer, the pixel-based representation to obtain first and second simulated images respectively corresponding to the first and second potential process window conditions; and 
 analyzing, using the computer, the first and second simulated images to determine deviations from a target design at the first and second potential process window conditions.